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g01d4 writes "On March 29, 2012, NASA scientists learned that the space agency's Fermi Gamma-ray Space Telescope was headed for a potential conjunction (close approach) with Cosmos 1805, a defunct Russian satellite from the Cold War era. The team knew that the only way to move Fermi would be to fire thrusters designed to move the spacecraft out of orbit at the end of its operating life. On April 3rd, shortly after noon EDT, the space agency fired all thrusters for one second. When it was over, everyone involved 'just sighed with relief that it all went well.' By 1 p.m., the spacecraft had returned to its mission."

No. It wasn't news then for the same reason there are no highly moderated posts on the article now: it isn't news. When this occurred the community (of gamma-ray astronomers) knew it was happening. It was never kept secret.

Nuke it from orbit, it's the only way to be sure. Not to mention that it's already in orbit.

Nice idea... simple solution... but if we take this seriously (sorry, too early in the morning for my sense of humour to have woken up yet) the only problem with it is that any explosive method of dealing with orbiting debris just creates lots of small and tiny pieces of shrapnel, and traveling through a field of that crap at orbital velocities is not going to be the highlight of your day. Not a problem if you are in an M1 Abrams battle tank, but satellites do not have armour, except for shielding against t

Dodged evidently doesn't mean it was going to hit it and they moved it out of the way. It was actually a "close approach" as stated in the summary (gotta love sensationalism, right?). Except, close approach actually means within 700' of the defunct satellite, which really isn't all the close at all.

Though Fermi was expected to miss Cosmos by several-hundred feet, NASA scientists knew from experience that forecasting spacecraft positions a week in advance isn’t an exact science. For example, Iridium 33 and Cosmos 2251 collided in 2009 even though they were predicted to miss each other by approximately 1,900 feet. This was the first known satellite-to-satellite collision.

700' is ridiculously close when you're going miles per second and the Earth's atmosphere is constantly changing, changing each object's orbits by similar amounts regularly due to drag.

Heck, if the RADAR producing the data has a couple of microseconds of jitter in it's clock, the propagation estimates could be off by that amount....Basically, 700' is pretty close to the noise of our estimations for orbital objects like this, and it's just better to be safe than sorry. Not to mention, who knows what small pi

Except, close approach actually means within 700' of the defunct satellite, which really isn't all the close at all.

Except, you don't know the margin of error in either our knowledge of Fermi's orbit or that of Cosmos 1805's orbit. But I'd be willing to bet that the margins are large enough that a predicted 700' approach would place the two spheres of position sufficiently in overlap that there was a non-zero chance of collision.

Actually, revised calculations made their pass even closer, within 30 milliseconds [csmonitor.com]. I may be doing the math wrong, but it seems like that's much closer, like an order of magnitude closer than 700' and then some.

It seems to have reached a point where the amount of orbital garbage is causing major (and expensive) problems.I think that if anyone puts a sat in orbit without dodging capability, they are fools, and potentially contributing to the 'littering' of orbitals.

It's past time to start working on and TESTING solutions to clean up the orbitals before it gets even more out of hand.

Or is this some Earthshade Anti-Warming scheme I missed hearing about?

In LEO, orbiting debris are a self limiting problem. They will eventually deorbit on their own. So I guess that's not an issue for you.

In Geosynchronous orbit, every object is going to be pretty much moving in exactly the same direction anyway so the relative velocity is really small. The risk of collision is pretty small and the debris created would be minimal at low collision energies.

Outside these two areas, collecting orbiting debris, which vary in size from a few tons down to a few grams is a daunting task at best. How do one would imagine this could be done is the stuff of science fiction at best. Any collection system would by definition need to collect varying sized objects passing though a huge (by human standards) volume. This means there will need to be some pretty large structures launched, flown in space, survive the impact of collecting the desired objects and dispose of the collected mass. All this will need to happen without adding to the problem....

I just don't see how we are going to do this.

Personally, mankind would be better off if we took a debris mitigation strategy that required all launched hardware be mindful of not creating debris in orbits that would not naturally reenter within 5 years or so. We do this kind of thing now, at least the responsible people throwing most of the stuff in to space do, no telling what DPRK does.

Other than that, we might want to start thinking about building "space tugs" that can capture the junk that's collecting in geosynchronous orbit, tug it to less popular locations and work on ways to recycle parts of it. It sure doesn't seem worth the effort to deorbit the stuff that is that high up.

If you want to be pedantic, no. "Geosynchronous" means that it has a 1-day orbital period but does not specify the inclination or eccentricity of that orbit. The correct term for what you're talking about is "geostationary".

The GP has a point. The GGP states they have little relative velocity, which means they would have to have the same inclination. A geosynchronous satellite that is moving in the opposite direction is going to have a ton of relative velocity and would have disastrous results in the event of a collision.

So perhaps the GPP meant geostationary (or close to it), not just geosyncronous (if the only definition of that is the satellite has a 1-day orbit). However, I am not an astrologer or any sort of scientist, so

Two effects of lasers could be useful, but I don't think either of them really helps in any useful way.

One, you could push an object with a laser. The effect is pretty small, but you could adjust an object's orbit by giving it a small push from time to time. I suppose you could eventually get it to re-enter if you can adjust the orbit enough over time. This would take a LONG time considering you would likely want the laser to be earth based so yo

Orbit. So easy to make an object leave it's orbit. Change is vertical moment. So, a ground based laser, solar powered, naturally, is used to target junk just under the base station. A few minutes a days and this junk will be coming down. Why are we waiting?

Because no one is willing to pay a gazillion dollars to provide bonuses to aerospace executives. Once the C-suite execs find a sponsor you'll suddenly hear what a high priority clearing out orbital debris has become.